Question

which of the following orthogonal listings correctly represents a right cervical lateral flexion?
a) -θy
b) +θx
c) +θz
d) -θx

Explanation:

To determine the correct orthogonal listing for right cervical lateral flexion, we analyze the axes and rotations:

• Lateral flexion of the cervical spine (bending side - to - side) is associated with rotation about the \(X\) - axis in some orthogonal coordinate systems used in spinal mechanics.
• For right cervical lateral flexion, the angular displacement about the \(X\) - axis is typically represented as \(-\theta X\). Let's briefly analyze the other options:
• Option a (\(-\theta Y\)): Rotation about the \(Y\) - axis is more related to flexion/extension or other rotational motions not lateral flexion.
• Option b (\(+\theta X\)): Positive rotation about the \(X\) - axis would correspond to left cervical lateral flexion (opposite of right).
• Option c (\(+\theta Z\)): Rotation about the \(Z\) - axis is related to axial rotation (twisting) of the spine, not lateral flexion.

Answer:

d) \(-\theta X\)